Hello me buying a dlc

[Whiskys]

Good Night everyone:
I recently bought crusader kings free 2 play, and i rollos the instructions to acquire old gods DLC, I have the key code, but I don't khow how to activate without buy it on store... I don't have the pc right now. So I must use app steam, and there no way to activate key before buy it. The app said me to pay with PayPal.

Somebody can help me to write the key code, please?

 

[Had a dad]

No idea how to activate a code on the phone app. Just wait till you have access to your PC and activate it there